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Collagen supplements, frequently asked questions answered by specialists

Collagen supplements, frequently asked questions answered by specialists

Published: 1 December, 2022 - Updated: 2 February, 2024 | 5'

Collagen is a protein that is found primarily in our bones, cartilage, tendons, joints, and skin. It is responsible for the structural integrity of our tissues and organs, promoting joint mobility and skin texture.

There are several types of collagen, with type I being the most abundant in the human body. We can obtain it through our diet, and we can also find collagen dietary supplements.

With the help of Dr. Álvaro Sanjuán, a specialist in sports medicine, rehabilitation, and Bone Densitometry; Dr. Yaiza Acosta, a sports doctor and nutritionist, and the person in charge of the Scientific Information area at MARNYS, María Mercedes Sánchez, we clarify some of the most common doubts related to collagen.

1. What foods containing collagen can I consume?

“Collagen is exclusively produced in animal organisms, mainly obtained from mammals and marine animals. A varied and balanced diet includes collagen in its composition, with meats (beef, chicken, pork or lamb, especially those that provide high biological value proteins, such as collagen found in skin or bone broth, chicken feet, pig trotters) being among the richest sources of collagen, as well as oily fish (tuna, sardines, mackerel or salmon with skin and bones). Eggs also contain collagen. Additionally, the vitamin C found in fruits and vegetables such as kiwi, orange, lemon, berries, and asparagus promotes collagen production in the body. And we must not forget nuts, especially walnuts, as they provide the amino acids our body needs to create collagen”, explains Dr. Acosta, a sports doctor and nutritionist.

2. What is the difference between collagen and hydrolyzed collagen?

“The difference is that hydrolyzed collagen has better absorption and assimilation in our body compared to ‘normal’ collagen. This is because hydrolyzed collagen is obtained from the breakdown of highly dense native collagen proteins, resulting in a mixture of collagen peptides (small chains of amino acids) with low molecular weight,” states María Mercedes Sánchez.

3. What is the difference between hydrolyzed collagen and collagen peptides?

“They are synonymous terms that refer, as mentioned earlier, to the most assimilable form of collagen for the body,” clarifies María Mercedes Sánchez.

4. What is the best collagen to consume?

Dr. Acosta suggests that: “given that collagen is a protein with a very high molecular weight, after ingestion, it must be previously digested to be subsequently assimilated by our body in the form of peptides and amino acids. To facilitate this process, dietary supplements containing hydrolyzed collagen are a good option if you want to consume this protein.”

5. What collagen should I take for bones and joints?

“The key is to have a varied and balanced diet, to which I suggest adding dietary supplements with hydrolyzed collagen (which is the one that is absorbed), along with ingredients such as magnesium, calcium, silicon, zinc, combined with vitamins (such as vitamin D and vitamin C, among others), which contribute to the maintenance of the structure and vitality of bones and joints,” adds Dr. Acosta.

6. What are the benefits of taking collagen supplements for bones?

As explained in this case by Dr. Álvaro Sanjuán, a family doctor specialized in sports medicine, rehabilitation, functional readaptation, and Bone Densitometry, “age, overweight, physical activity or sports injuries, and occupational injuries, among other factors, can result in a loss of type I collagen. The oral intake of hydrolyzed collagen from the diet or in the form of dietary supplements provides proteins that are part of the structures of cartilage, tendons, and ligaments (connective tissues) and promotes their elasticity and lubrication.”

7. For joints, what is better: collagen or magnesium?

“Both are allies in osteoarticular and muscle well-being. Collagen is the basic structure of the entire osteoarticular system, and its contribution favors its functioning, particularly in terms of regeneration, elasticity, and lubrication. Magnesium, on the other hand, is the body’s ‘natural relaxant’, and therefore facilitates and enhances these characteristics,” clarifies Dr. Sanjuán.

8. When do the effects of collagen start to be noticeable?

Collagen effects

“Studies conducted with the ingestion of 5g of collagen reveal positive effects after 4 weeks of use,” states María Mercedes Sánchez.

9. What collagen supplements should I take for the skin?

“It has been shown that after oral administration, the bioavailability of hydrolyzed type I collagen is 90% in the skin. Thus, nutricosmetics with hydrolyzed collagen are, along with a balanced diet, a good option as they act from within, promoting nourishment, hydration, firmness, and smoothness of the skin,” explains the responsible for Scientific Information, Maria Mercedes Sanchez.


10. What benefits does taking collagen supplements have for the skin?

“Up to 40% of the collagen in our body is found in the skin, and its quantity and density decrease with age. Taking dietary supplements with collagen, along with a varied and balanced diet, can favor its presence in the skin, facilitating the optimal production of collagen fibers for a youthful and healthy appearance,” affirms Sanchez.

11. How much collagen is usually consumed daily?

“The most commonly used daily amounts vary between 2.5 and 10 g of collagen per day,” indicates specialist Maria Mercedes Sanchez.

12. What happens if I take collagen every day?

Specialists agree that collagen supplements can be taken for long periods of time without apparent discomfort.

13. When is the best time to take collagen, in the morning or at night?

Specialists also agree that collagen can be taken at any time of the day, indistinctly.

14. Who should not take collagen?

As Maria Mercedes Sanchez clarifies, “collagen is a component naturally present in our body and has no contraindications at the recommended doses. In the case of pregnant or lactating women, they should consult with their doctor or healthcare professional.”

15. When taking collagen, should I take breaks?

“The general recommendation is to take it for a quarter and evaluate the results, then, if necessary, continue the intake. If you have any doubts, consult your doctor or healthcare professional,” concludes the responsible for Scientific Information, Maria Mercedes Sanchez.


Content prepared by specialists from the Scientific Information area of MARNYS with the collaboration of Dr. Alvaro Sanjuán and Dr. Yaiza Acosta. This article is informative and does not substitute the consultation of a specialist.

Dr. Yaiza AcostaAbout the Specialist

Dr. Yaiza Acosta @dra_saludable

The Dr. Yaiza Acosta holds a degree in medicine and surgery, specializing in physical medicine and sports medicine from the University of Barcelona, and in applied nutrition and dietetics. In addition, she promotes healthy lifestyle through her social media accounts as @dra_saludable.

Dr. Álvaro SanjuánAbout the Specialist

Dr. Álvaro Sanjuán

Dr. Álvaro Sanjuán is a medical doctor specialized in sports medicine, rehabilitation, and bone densitometry.

Health Specialists